(1) Field of the Invention
This invention relates to scanners, particularly to the paper guide of a scanner.
(2) Brief Description of the Related Art
FIG. 1 shows a prior art paper guide for a scanner. The paper guide is mounted over the scan window 24 of on top of the scanner frame 20. The paper guide has an upper guide 10, a lower paper inlet guide 11, a lower paper outlet guide 12, and a transparent film 23 between the inlet guide 11 and the outlet guide 12, as shown in FIG. 2. One end of the transparent film 23 connects to the lower surface of the outlet end 112 of the inlet guide 11, while the other end of the transparent film 23 connects to the upper surface of the inlet end 121 of the outlet guide 12. When a document P is fed from the lower paper inlet guide 11 past the transparent film 23, a light beam from the light source L is reflected by the paper as a beam 21 to sensitize an image sensor 22 for further signal processing. It can be seen that the lower guide includes three parts, the inlet paper lower guide 11, the transparent film 23, and the outlet paper lower guide 12. The transparent film 23 adds to the cost of a scanner, and is subject to rubbing during use, which may blur the film in time to obstruct the incident light.
An object of this invention is to reduce the cost of the paper guide of a scanner. Another object is to prevent the blurring of the transparent film of a scanner. Still another object is to optimize the amount of light incident on the document being scanned.
These objects are achieved by eliminating the transparent film. The inlet lower guide overhangs over the outlet lower guide. When the document is transported past the gap between the two lower guides, the document is read.